A hearts and arrows pattern is successfully generated from within a round cut diamond when exposed to light, provided that the round diamond has a nearly perfect symmetrically round shape possessing equal and symmetrically cut facets polished within relatively narrow proportional ranges, as taught below in Table I. A near perfect round cut diamond having a hearts and arrows pattern provides brilliance, color and optical light handling properties which has not been matched in the marketplace by any other shaped diamond to date. Although diamonds are typically cut into many known geometrical shapes other than round such as, for example, a heart shape, oval, pear, marquis, princess, emerald, etc., it is currently unknown to cut a diamond into a hexagonal shape much less in a manner to yield a hearts and arrows pattern substantially comparable to the hearts and arrows pattern generated by an ideal round cut diamond when exposed to light.
It is widely believed in the diamond industry that only the round cut diamond can generate a true hearts and arrows pattern. This belief is primarily based upon the fact that the round cut diamond has such a nearly perfect symmetrical shape and that all of its crown and pavilion facets can be readily cut to the same angle degrees with the angle differences between all of its pavilion angles being smaller than 0.3°, and with the angle tolerance between the main crown facets being smaller than 0.4° and the angle tolerance for the subsidiary crown facets being smaller than 0.3°. This rational lies has led to the widely accepted belief in the diamond industry that it is not possible to obtain a true hearts and arrows pattern on any shape which is not polished to simulate the nearly perfect symmetrical shape of a round shape and to satisfy the narrow angular tolerances known to yield a hearts and arrows pattern in a round cut diamond.
A hexagon shaped diamond has a geometrical shape which is clearly quite different in angular geometry from that of a round diamond and in fact, to date, it is currently unknown to cut a diamond into a hexagon shape. Moreover it is clearly unknown how one would create a hearts and arrows pattern in a hexagon shaped diamond particularly if one accepts the widely accepted belief in the diamond industry that the diamond should be cut to satisfy the narrow angular tolerances known to yield a hearts and arrows pattern in a round cut diamond.
In a round cut diamond, the hearts and arrows pattern appears only when the requirements for its cut facets, angle parameters and alignment relationships are as shown in the following Table 1:
TABLE 1The shape of the diamond is perfectly symmetrical8 main crown and 24 subsidiary crown facets8 main bottom and 16 subsidiary bottom facetsAll main facets (crown & bottom) have to be polished at a perfect 45°angle to each otherAll facets are perfectly alignedAll the bottom main facets are of equal size and at an angle rangingfrom 40.6°-41.0°All the bottom subsidiary facets are of equal size and at an angle whichis exactly 1.2° steeper than the main facets (main bottom angle40.6°-41.0° + subsidiary 41.8°-42.2°)All the main crown facets are of equal size and at an angle rangingfrom 33.8°-35.1°. They have to be perfectly aligned on the mainbottom facets.All the subsidiary crown facets are of equal size and perfectly alignedon the main crown and subsidiary bottom facets and polished at anequal angle.The ideal cut proportions are:total depth 59.4%-62.4%crown height 14.5%-16.0%girdle thickness 1.5%-2.95%Roundness 99.0%-100%Table size: 53.0%-57.5%